What is the maximum bore of a 400? If I wanted to bore my 400 which i do, then what would the final CID be? I'm talking about the full maximum bore the biggest bore possible.

 

[updated:LAST EDITED ON 30-Mar-02 AT 11:45 AM (EST)]Well they say if you want to be safe then just go .030 over. that will give you 409 Cubic Inch

I Myself have my blocks bored .060 over for my pulling trucks motors 435 CID and I have read someone bored it over to .080 but I think I'd have over heating problems and cracking problems with it that big of a bore.But it would give me 440 CDI out of my 4.200 stroked 400.

 

I had my 400 bored 0.60 over and it runs on the warm side. In the winter it seems normal but, in the summer the temp gauge stays close or on the "L" in normal( on the Factory Gauge )especially in stop 'N' go traffic. I will say this though, it has never boiled over on me since i've rebuilt it about 4 years ago. Good Luck, Rob

 

generally speaking .030 is fine, .060 is about max, but sonic check the block, and i have heard some people going to .080/.090, but dont expect it to last.

 

are the cylinder jackets on the 400 thicker than on the 351C? Roush recommends no more than +0.030 on a 351C intended for performance use, so I would expect similar limits on a 400 unless, as I mentioned, they have thicker jackets.